Abstract: A portable electronic apparatus has a display, keypad, sensor and controller. Keys of the keypad are distributed within a keypad area in at least a first plane and are arranged for user actuation transversally to the first plane to provide a first type of user input. The sensor is positioned to sense navigating user actuation at the keypad area in or coincident with the first plane to provide a second type of user input. The controller is configured to control a focus position on the display in response to the second type of user input; associate a plurality of display subareas of the display with respective keys of the keypad; and accept, for user input of the second type, user actuation of an actuated key among the keys as a selection of a selectable item presented at the focus position in a particular display subarea associated with the actuated key.

Abstract: A block (300) of image elements (310) is compressed by determining multiple base vectors (510, 520, 530, 540) based on the feature vectors (312) associated with the image elements. Additional vectors (560, 570) are calculated based on defined pairs of neighboring base vectors (510, 520, 530, 540). A vector among the base vectors (510, 520, 530, 540) and the additional vectors (560, 570) is selected as representation of the feature vector (312) of an image element (310). An identifier (550) associated with selected vector is assigned to the image element (310) and included in the compressed block (500) which also comprises representations of the determined base vectors (510, 520, 530, 540).

Abstract: A compressing of a texel block (10) consisting of two texel sub-blocks (12, 14) involves determining respective value codewords (31, 32) and table codewords (33, 34) for the two texel sub-blocks (12, 14). The value codewords (31, 32) represent respective base texel values and the table codewords (33, 34) represent respective modifier sets comprising multiple value modifiers for modifying the base texel value associated with the given texel sub-block (12, 14). Each texel (20) in the texel block (10) is assigned a texel index associated with one of the value modifiers of the modifier set for the texel sub-block (12, 14) to which the texel (20) belongs or indicates that the base texel value of the other texel sub-block (12, 14) is to be used for the texel (20).

Abstract: Embodiments relate to compression and decompression of textures. A texel block (10) is compressed by specifying two major directions in the texel block (10) and defining the profiles of how the texel values change along the respective directions. The resulting compressed texel block (30) comprises two value codewords (31, 32), two line codewords (35-38) and a function codeword (33, 34). The two value codewords (31, 32) are employed to calculate two texel values for the texel block (10). The line codewords (35-38) are employed to determine equations of two lines (20, 22) coinciding with the two major directions in the texel block (10). Signed distances are calculated for each texel (12) from the texel position in the texel block (10) and to the two lines (20, 22). The signed distances are input to a function defined by the function codeword (33, 34) to output two values from which weights are calculated and applied to the two texel values in order to get a representation of the texel value of a texel (12).

Abstract: First and second codewords are determined, based on first feature vector components of the image elements in an image block, as representations of a first and second component value. Third and fourth codewords are determined, based on second vector components, as representations of a third and fourth component value. First N1 and second N2 resolution numbers are selected based on the relation of a distribution of the first vector components and a distribution of the second vector components. N1 additional component values are generated based on the first and second component values and N2 additional component values are generated based on the third and fourth component values. Component indices indicative of the generated component values are then provided for the different image elements.

Abstract: A pixel block is compressed by providing a respective color component prediction for each pixel in the block. A difference between color components of two neighboring pixels is calculated and compared to a threshold. If the difference is smaller than the threshold, the prediction is calculated based on a first linear combination of the color components of these two neighboring pixels. However, if the difference exceeds the threshold, a second or third linear combination of the color components of the neighboring pixels is employed in the prediction. A guiding bit associated with the selected linear combination may be used. A prediction error is calculated based on the color component of the pixel and the provided prediction. The compressed block comprises an encoded representation of the prediction error and any guiding bit.

Abstract: Multi-mode decoding and encoding of texture blocks are disclosed wherein in a default decoding and encoding mode all bits of a codeword sequence are available as payload bits for representing texel values of the texels in the texture block. In an auxiliary encoding and decoding mode one less bit of the codeword sequence is available as payload bits. The auxiliary mode is employed as a complement to the default mode and will be used to process those texture blocks, which the default mode handles poorly.

Abstract: A portable electronic apparatus (300) has a display (320) and a keypad (340) with a plurality of keys (342), the keys being distributed within a keypad area (341) in at least a first plane, and the keys being arranged for key-pressing user actuation transversally to the first plane so as to provide a first type of user input. The apparatus also has sensor means (430, 450, 348) positioned to sense navigating user actuation at the keypad area in or coincident with said first plane so as to provide a second type of user input, and a controller (301) configured to control a focus position (323) on the display (320) in response to user input of the second type.

Abstract: A pixel block (300) is losslessly compressed into a candidate compressed block. If the bit length of the candidate block exceeds a threshold value, the property values of the pixels (310-317) in the block (300) are quantized and the quantized values are losslessly compressed into a new candidate compressed block. The procedure is repeated until a candidate compressed block having good image quality and a bit length below the threshold value is found. A compressed representation (400) of the block (300) is determined based on the found candidate compressed block (420) and an identifier (410) of the used quantization parameter.

Abstract: A pixel block is compressed by providing a respective color component prediction for each pixel in the block. A difference between color components of two neighboring pixels is calculated and compared to a threshold. If the difference is smaller than the threshold, the prediction is calculated based on a first linear combination of the color components of these two neighboring pixels. However, if the difference exceeds the threshold, a second or third linear combination of the color components of the neighboring pixels is employed in the prediction. A guiding bit associated with the selected linear combination may be used. A prediction error is calculated based on the color component of the pixel and the provided prediction. The compressed block comprises an encoded representation of the prediction error and any guiding bit.

Abstract: A pixel block (300) is compressed by selecting a start depth value and a restart depth value based on the multiple depth values of the pixels (310-318) in the block (300). A respective plane representation (430) indicative of which plane of a start or restart depth value plane is determined for the pixels (311-318). These representations (430) are employed for selecting a pixel set comprising at least one other pixel (312, 314-317) in the block (300) for a pixel (318) to be encoded. The depth value(s) of the pixel(s) (312, 314-317) in the set are used for determining a prediction of the depth value of the pixel (318). The depth value and the prediction are employed for calculating a prediction error, which is encoded. The compressed pixel block (400) comprises the encoded prediction errors (460), a start value representation (420), a restart value representation (430) and the plane representations (440).

Abstract: A decoding system comprises N different decoders each having a unique circuitry that is different from the circuitries of the other N?1 decoders. The decoders each generate at least one texel value based on an input encoded texel block. A value selector is configured to selectively output at least N texel values from at least one of the decoders based on the position of the at least N texels relative a boundary of a texel block comprising at least one of the at least N texels. A pixel calculator calculates a pixel value of a decoded pixel based on the at least N selected texel values from the value selector.

Abstract: A block (300) of image elements (310) is compressed by identifying a base vector (460) based on normalized feature vectors (312) of the block (300). If a position-determining coordinate (420) of the base vector (460) is present inside a defined selection section (530) of feature vector space (500), the block (300) is compressed according to a default mode and an auxiliary mode to get a default and auxiliary compressed block (600), respectively. The compressed block (600) resulting in smallest compression error is selected. If the auxiliary mode is selected, the position-determining coordinate (420) is mapped to get a mapped coordinate (425) present outside the representable normalization portion (510) of vector space (500). The auxiliary compressed block (600) comprises a representation of this mapped coordinate (425). If the default mode is selected no such coordinate mapping is performed and the default compressed block (600) instead comprises a representation of the non-mirrored coordinate (420).

Abstract: Device, computer readable medium, and method for selecting compression modes to be applied in a depth buffer (20).

Abstract: An image block comprising multiple image elements is compressed into at least one base codeword, interval codeword and index sequence. The respective bit-length of at least two of the codewords and the index sequence are dynamically defined based on the original vector components of the image elements, though the total bit length of the resulting compressed block is constant. The base codeword represents a base value and the interval codeword represents an interval. This interval encompasses multiple component values relative the base value. The index sequence is indicative of, for each image element, a component value selected from the multiple available values.

Abstract: Compression of a pixel block having multiple pixels comprises calculating a respective prediction error for each pixel component of the pixels except a defined starting pixel. Respective minimum number of symbols required for representing the prediction errors are determined and used to select a symbol configuration among multiple different symbol configurations. Each such symbol configuration defines respective numbers of symbols maximally available for the different prediction errors. A compressed representation of the pixel block comprises a configuration identifier of the selected symbol configuration, a representation of the pixel value of the defined starting pixel and representations of the prediction errors calculated for the remaining pixels.

Abstract: The present invention relates to methods and arrangements for compressing images. The invention is based on the fact that edge blocks contain much information in one direction (across the edge), but very little information in the other direction (along the edge). By encoding edges explicitly, it is possible to obtain a high quality to a very low cost for many blocks. A block is encoded by first specifying the orientation of the edge in the block, and then specifying the profile across the edge using a function with a small number of parameters.

Abstract: In an image-encoding scheme, an input image is decomposed into image blocks comprising multiple image elements. The image blocks are then encoded into encoded blocks. An encoded block comprises a first color codeword, a second color codeword, a color modifier codeword and a color index sequence. The color codewords are representations of a first and second base color located on a first line in color space. The modifier codeword is a representation of at least one color modifier for modifying the first base color along a second line to obtain multiple color representations along the line. The second line has a different direction as compared to the first line. The index sequence comprises color indices associated with a color representation selected form i) the representations on the second line and ii) at least one representation based on the second base color.

Abstract: A pixel block (300) is compressed by sub-sampling at least a portion of the pixels (310) into subblocks (320, 330). Predictions are determined for the property values of these subblocks (320, 330) by calculating a variance measure based on property values of neighboring pixels (310)/subblocks (320, 330) in two prediction directions in the block (300) relative to a current subblock (320, 330). If the variance is below a threshold, the prediction is calculated based on neighboring property values in both directions. If the measure exceeds the threshold, the neighboring property values in only one of the two predictions directions are used for calculating the prediction. A guiding bit (450) descriptive of the selected direction is also provided. A prediction error is calculated based on the property value and the calculated prediction. The compressed block (400) comprises an encoded representation (460) of the prediction error and any guiding bit (470).

Abstract: A blurred barcode image is processed by providing an image representation thereof comprising grayscale values. The image representation is deconvoluted using a candidate motion kernel to get a deconvoluted representation. A barcode similarity measure is calculated for the deconvoluted representation to indicate how close the distribution of the grayscale values of the deconvoluted representation is to an optimal distribution for a barcode image.